1. Field of the Invention
This invention relates generally to data input on electronic devices, and in particular to input of ideographic Korean syllables from reduced keyboards.
2. Description of the State of the Art
The Korean language, like most Asian languages, is comprised of thousands of symbols, making it impossible to represent all the symbols on a keyboard. As such, several keystrokes are normally required to enter a single symbol. For example, Korean symbols include basic Jamo characters, compound Jamo characters, and Hangul syllables. Compound Jamo characters and Hangul syllables are built from basic Jamo characters. The basic Jamo characters include 19 leading consonants, 21 vowels, and 28 trailing consonants, whereas the total number of possible Hangul syllables is 11,172.
When reduced keyboards or keypads containing multiple-character keys, such as those found on electronic devices, are used for Korean text input, this problem is further compounded. Entry of each basic Jamo character typically requires a user to depress a single key multiple times, and entry of a compound Jamo character or Hangul syllable requires entry of several basic Jamo characters. Therefore, entry of a single symbol may require many keystrokes.
In order to alleviate the problem of character composition, input methods were designed and developed, containing the required logic for the Korean language based on composition rules, to convert keystrokes of users into appropriate symbols. However, these conversions according to known input methods are often ambiguous or incorrect, forcing a user to either select an intended symbol from a plurality of possible symbols generated by the input method or correct an incorrect symbol generated by the input method. Such symbol selection or correction makes text input slow and tedious, and the use of devices with reduced keypads very inconvenient.